New Flavones from the Stem Bark of Morus alba L.

Morus alba L. (Moraceae) is a perennial, heterogenous out breeding tree or shrub commonly known as mulberry [1,2]. It is indigenous to China and extensively cultivated throughout Eastern, Central, and Southern Asia. Mulberry is known to have antimicrobial, antioxidant, antidiabetic, neuroprotective, skin tonic, immunonutrition and anticancer activity. The bark of the large stem is brown, rough, fibrous, fissured mostly vertical, and is used as a vermifuge and purgative [3,4]. Mulberrochomene, cyclomulberrochromene, mulberrin, cyclomulberrin, mulberranol, albanol A and B, β-sitosterol, α-amyrin, β-amyrin, phytol and lupeol have been reported from the stem bark [5,6,7]. The present study deals with the isolation of two new flavones characterized as 5,4'-dihydroxy-7-octadec-9-enoxy-8-(ã-methylallyl)-2',3'-(2''', 3'''-dimethylpyr-1'''-enyl) flavone and 5,7,4'-trihydroxy-8-(ã-methylallyl)-2', 3'-(2''', 3'''-dimethylpyr-1'''-enyl) flavone along with the known compounds α-amyrin acetate, β-amyrin-β-D-glucopyranoside and betulinic acid from the alcoholic extract of M. alba stem bark from the Delhi region. The structures of compounds have been established on the basis of FAB-MS, 1D-NMR (¹H-NMR, ¹³C-NMR) and 2D-NMR (¹H-¹H COSY, HMBC) spectroscopic techniques and chemical reactions. Acknowledgements: The authors are thankful to the Head, SAIF, Central Drug Research Institute, Lucknow, India, for instrumentation facility. References: [1] Anonymous, (2001) The Wealth of India: A Dictionary of Indian Raw Materials and Industrial Products. New Delhi: CSIR, 6(L-M): 429–437. [2] Weiguo Z, Zhihua Z, (2007) A comparison of genetic variation among wild and cultivated Morus Species (Moraceae:Morus) as revealed by ISSR and SSR markers. Biodiversity and Conservation, 16: 275–290. [3] Mhaskar KS, Blatter E, (2000) Kiritikar and Basu illustrated: Indian Medicinal Plants, there usage in Ayurveda and Unani medicines. Delhi: Sri Satguru Publications, 10: 3185–3187. [4] Butt MS, Nazir A (2008). Trends in Food Sci and Tech 19: 505–512. [5] Deshpande VH, Parthasarathy PC (1968) Tetrahedron letters 9(14): 1715–1719. [6] Rama Rao AV, Deshpande VH (1983) Tetrahedron Letters, 24 (29), 3013–3016. [7] Boszormenyi A, Szarka Sz (2009) Acta Chromatographica 21(4): 659–669.